While your in-role personality and demeanour will be largely a matter for you to portray through the things you say and the actions you perform (i.e. if you are a nasty murderous type you will attack folks unprovoked; if you are a kindly altruist you will protect folks without need for reward). This is the beauty of a game like Avalon where your 'roleplay' is also - in a sense - a 'realplay': you are defined not by arbitrary labels applied to your character but by your interactions with others and your character's unfolding history. People will judge you on what you do, not what badges you wear.
There are two commands you should know, however, useful to inform Avalon itself of your chosen demeanour/outlook: FRIENDLY and HOSTILE. When you type FRIENDLY and thereafter place your character in 'friendly' mode, various circumstances will presume your intentions and outlook are open and ingenious. Example: if you are following someone in friendly mode and they type GROUPSTATUS they will see you in their entourage. When you type HOSTILE, on the other hand, Avalon will thereafter place your character in 'hostile' mode and your intentions will be presumed secret and unfriendly. Example: if the self same person types GROUPSTATUS when followed by someone in 'hostile' mode, they will not see the individual in their entourage.
Friendly folks when followed will lead followers as safely as possible as they move around, whereas hostile types when followed will presume followers are unwanted and make no effort to keep them safe. This may seem a minor distinction but imagine you are skilled in flight and you fly up into the skies while followed by someone. If you are FRIENDLY then you will hold that person's hand and ensure they can be led safely across the heavens, but if you are HOSTILE the follower will trail you up into the skies but unless he/she has independent means of flying activated, the poor person will tumble to the ground! HOSTILE mode ensures you do not easily follow by teleport into overtly hostile or restricted (i.e. trapped/fatally dangerous) destination locations. See HELP FOLLOW for details on this.